1. Field of the Invention:
This invention relates to the field of flat bed trucks. More particularly, this invention relates to trucks with multi-position beds. Even more particularly, this invention relates to trucks with powered multi-position beds.
2. Prior Art:
Trucks with flat beds are, generally, used for transporting all kinds of items and have been in use since the first days of truck manufacturing. Flat beds on the truck are, generally, fixed beds with limited or no movement.
However, some flat beds trucks have been equipped with lifts, such as hydraulic lifts, as well as split beds. With lifts, they are used to raise the front of the bed causing it to tilt toward the stationary or fixed rear of the bed. This permits any item, such as sand, gravel or the like, to be dumped from the flat bed at one time.
Furthermore, flat bed trucks have been used to transport large objects, such as vehicles, including automobiles, tractors and other self-powered vehicles. Loading and unloading these vehicles onto and from the flat bed of the truck has been accomplished by many methods.
One such method is to use a pair of manually positioned, spaced apart wheel ramps or a single ramp having one end thereof on the truck bed, the other end on the ground. The vehicle is then driven, pushed, or towed up the ramp to the desired position on the flat bed. The vehicle is, then, fixed in position and the ramp is removed.
Another method, regularly in use, and which requires little or no manual operation, employs a powered tailgate or rear platform located at the back end of the flat bed. The powered tailgate is of sufficient size to provide a loading ramp when lowered from the back end of the flat bed to the ground. When it is lowered to the ground, it performs as the manually positioned ramp or ramps perform. Then, the tailgate is raised and driven onto the bed and fixed in position for transport.
A further method for loading a flat bed truck is to back the flat bed against a stationary loading platform which is the same height as the truck. This permits the vehicle to be driven directly onto the bed.
All of the above methods are in common use, but each of the methods presents its own problems or use restrictions. Positionable ramps, whether manual or automatic, limit the bottom clearance for loading vehicles and cause damage to the undercarriage of those vehicles having a low road clearance. Stationary ramps are not always available at loading and unloading points. Thus, a flat bed truck which permits the loading and unloading of any type vehicle and which does not require ramps of any kind would be desirable. Moreover, to provide all of the advantages within a single flat bed truck would be highly desirable. It is to this to which the present invention is directed.